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An anonymous reader writes "At Imperial College London, researchers have embarked on a £1m project to study, and eventually mimic, photosynthesis. Part of the 'artificial leaf' project involves working out exactly how leaves use sunlight to make useful molecules. The team then plans to build artificial systems that can do the same to generate clean fuels such as hydrogen and methanol. These would then be used in fuel cells to make electricity or to directly power super-clean vehicles."

I plan on creating a bee suit to let 300 pound people fly.
Oh, good. I think that has a MUCH better chance of happening then our moving towards a hydrogen economy. The simple fact is, that hydrogen is actually WORSE than any other options. Even right now, current in production Batteries are already better than what hydrogen can or ever will do.

Oh, good. I think that has a MUCH better chance of happening then our moving towards a hydrogen economy. The simple fact is, that hydrogen is actually WORSE than any other options. Even right now, current in production Batteries are already better than what hydrogen can or ever will do.

Mebbe so, but you still have to come up with a way to recharge those batteries. Mebbe hydrogen isn't the best solution, however, it can power a generator to recharge

Is that not what plants have been doing since the beginning? To mimic a process, one first has to understand it. Scientists have been trying to understand exactly how photosynthesis works. I can so many things, a vague understanding is not good enough, but the devil is in the details. Scientists do have some idea about how photosynthesis works, but on the deepest atomic level, they still don't know enough to actually make an artificial leaf. I wish thes

Mebbe so, but you still have to come up with a way to recharge those batteries. Mebbe hydrogen isn't the best solution, however, it can power a generator to recharge said batteries.

There's no reason to introduce hydrogen into the process you describe, unless you have a pre-existing source of hydrogen gas (IE skimming it off of Jupiter). Otherwise you're just wasting efficiency by not charging the batteries directly using whatever power you used to run the hydrogen generator.

Hydrogen is LOADED with all sorts of isses. For starters, it is by far the most inefficient transportation. Even now, batt/caps are the most efficient. Far fare more than oil/CNG/ LPG/ Hydrogen, etc. Their are several issues with electricity. The first is costs. It is too high. But that is coming down. The second is time to charge. That will remain high as long as we are doing batteries. At some pooint, it is very likely that caps will be low costs and have high energy density. There are already 3 solution

So, can wind, geo-thermal, solar, Coal, nukes, etc. And ALL of those items are needed to generate the energy to separate hydrogen from water (or even a fossil fuel). AND the total cycle of electricty->transportation->battery->motor is STILL far more efficient than is electricity->(fossilfuel|water)->hydrogen->transportation->various storage->(fuel cell|engine|etc).

How exactly did we obtain that clean supply of hydrogen? And I am talking in terms of TODAY as well as say another 20 years, rather than saying by fusion power? If you look at the efficiency of that cycle, it is, and will remain, inefficient. At least until we can obtain hydrogen for free, which is not likely to happen.

I wasn't saying that hydrogen production was clean & renewable today. Assuming that this technology (or another renewable hydrogen-producing technology) someday proves viable, I was wondering what you saw wrong with hydrogen vs. batteries.

For the most part, yes. I object to those pushing hydrogen as being the end all, when in reality we are decades away from having so many of the minor issues, let alone some of the major ones, solved. For example, right now, somewhere between 90-100% of all commercially available H2 is by stripping it from hydrocarbons. What happens to the C? it is released as CO2. IOW, hydrogen does nothing to solve the carbon issue. So, lets assume that we want to have less oil being

Seeing as Hydrogen is the source of the vast majority of the entire known universe's energy... I think you need to reexamine that statement. Hydrogen is what we're trying to use for Fusion technology, and Hydrogen is very efficient at storing energy for later use. Much more efficient than batteries.

First, I doubt that you will have a small fusion reactor in our cars anytime soon.
Second, Hydrogen, currently, has higher energy density, BUT has issues with storage, as well as usage (motors are very inefficient and fuel cells are a LONG ways off). LONG before hydrogen issues are solved, batteries will have a higher energy density (assuming that hydrogen can not be compressed infinitly).

Hydrogen, currently, has higher energy density, BUT has issues with storage, as well as usage (motors are very inefficient and fuel cells are a LONG ways off). LONG before hydrogen issues are solved, batteries will have a higher energy density (assuming that hydrogen can not be compressed infinitly).

Fuel cells are currently being used in cars today [honda.com], so they are definitely NOT a "LONG ways off".

All of your complaints are just complaints, that have already been addressed. It's FUD.

Electric motors are far more efficient at converting power to usable kinetic energy than gasoline engines, yet you actually try to bring this up? Are you "that guy" who makes up non-issues? Sure sounds like it. Hell, if you're so convinced that current engines are so efficient, they can just burn the hydrogen instead.

The problems with hydrogen is getting it and storing it. I think it was myth busters where I saw them pump hydrogen gas into a car engine and it ran. Well, it ran until the gas leaked out of the engine since said engine was not made for hydrogen gas.

Isn't Iceland going all hydrogen? Cars, boats, just about everything? Granted Iceland has a lot of geothermal based electricity on hand to make the hydrogen. Other places in the world also have geothermal energy available (the west cost of the US for one). The

Actually, there is much more than that. For starters, nearly all of the current hydrogen comes from stripping it from Oil or CNG. This is funny, because you take it off and then release the CO2 that was created. Yet, it would have been far more efficient to flat out burn it.

The other approach is obviously to split it from water. BUT, this is VERY energy intensive, and will remain, there is no real way around this; you have to break the bonds. Obviously as you point out is the issue of the transportation

In the end, it is currently FAR FAR cheaper to take that initial electricity, send it over a poor wire, store it in a lead acid battery and then use a 98% efficieny motor. Basically, all of those pushing Hydrogen are not just ignoring state of the art, but simple physics.

A 98% efficient motor? But you stated here [slashdot.org] that electric "motors are very inefficient and fuel cells are a LONG ways off". Both of which are wrong.

I'm not exactly chasing you around trying to debunk you, but you've really only said one thing on this thread that was correct, and that is that there are issues with distribution and production of hydrogen (i.e. a hydrogen economy). It's true that there aren't many refilling stations. It's true that hydrolysis of water takes a lot of energy or is produced fr

It staggers the mind to think of the amazing technological advances we've made but we still haven't taken the time to unlock the secrets of photosynthesis. Given environmental concerns, I thought this would have been done a long time ago.

> I thought we were talking about a feature missing in an FOSS package.But aren't we?

AFAIK there's no reason any joe off the street can't go do photosynthesis research and post his findings. Funding and specialized advanced degrees are real nice to have, but they're technically not part of the scientific method.

Well, a lot is known about how photosynthesis splits water (though many of the discoveries are comparitively quite recent), but "unlocking the secrets" really refers to being able to do it on our own terms, using the materials available to us. Where living things use enzymes, we are largely forced to substitute inorganic catalysts. That may change somewhat as advances in bioengineering are made, but photosynthesis in particular is a process that involves so many integrated systems and molecules that the b

Photosynthesis has traditionally been one of the "hard" problems to solve. These guys are going to figure it out for 1 million pounds and then use it to produce fuel? I'll put my money on cold fusion first.

Except that this is not about genetics, but artificially trying to duplicate photosynthesis. That is before you can duplicate something, you have to know something about it and science doesn't know that much about exactly how a photon of light is used in a green leaf or algae with chlorophyll to knit carbon and hydrogen together into a hydrocarbon.

They're not trying to duplicate photosynthesis... they're ignoring the synthesis part. They just want to understand how the cell uses sunlight to split the hydrogen and oxygen in water. The quickest path to achieve this might be to simply determine what proteins are doing the work and what they require to function. Then, once you know this, replicate the appropriate proteins on an industrial scale. Replicating the proteins would be a job for the genetic engineers. Hence, my suggestion that genetic eng

Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a chemical compound with chemical formula CH3OH (often abbreviated MeOH). It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid

Sounds like a carbon-based fuel to me. Not sure why it's considered "clean". But at least we're not digging the carbon out of the bowels of the earth before we spew it into the sky.

If you get it by removing the same quantity of carbon from the air (which is what photosynthesis does), it's carbon-neutral. It's clean because it doesn't contain things other than methanol, and the combustion products of methanol are relatively harmless.

We are using SMALL amounts of alcohols in our fuels to oxygenate the burning. Problem comes in when it is the primary form of fuel. Then you will ALWAYS have partial burning. As you point out, ethanols are converted into a number of side products which includes aldahydes. In small amounts, overall not a big deal (though still not great). But in large amounts These are ABSOLUTELY WICKED.

I would guess that they are intending to use the methanol on a fuel cell rather than a regular internal combustion engine. Fuel cells produce essentially nothing but co2 and water. It should also be fairl easy to put a catalytic converter on the exhaust to remove any traces of methanol. Over all I think methanol could be a great fuel.

The link says that one of the intermediate products of methanol combustion is formaldehyde. Who cares if formaldehyde is produced and immediately burned inside the engine? What matters is how much comes out the tailpipe. It seems that alcohol fuels [wikipedia.org] do produce somewhat more aldehyde than gasoline, but they produce somewhat lower amounts of other pollutants.

The problem with any internal combustion engine is it's hard to control the combustion process so completely that you don't get any intermediate products out the tailpipe.

The GP said "the combustion products of methanol are relatively harmless" and that's the part I'm taking issue with - I think that because methanol can be cheaply synthesized from a number of different feedstocks, it's a good candidate for a gasoline substitute, and I've actually used M-85 blend in my race car. The higher octane number of

Just read TFA and it looks like the project's goal is not to remove CO2 from the atmosphere, but to find out how to use sunlight as an energy source to synthesize molecules.

Over here, across the pond, we've got a team of Yanks already working on the other side of the carbon equation: Artificial leaves to capture CO2 from the air. And, in typical Yank fashion, its being done by private enterprise [grestech.com].

We are looking for carbon-based fuels to replace fossil fuels. That's what biofuels are. I don't know of any energy source that can power airplanes other than carbon-based fuels.

When methane is used as a fuel, the waste gases are water vapor and carbon dioxide. If the carbon in the methane recently came from the atmosphere, it will not cause a net increase in the concentration of carbon dioxide in the atmosphere.

> I don't know of any energy source that can power airplanes other than carbon-based fuels.Your unawareness of alternatives doesn't mean that carbon is a requirement for flight. Consider these planes:Hydrogen [gizmodo.com] Solar [pvresources.com] Electric [youtube.com]

Well, yeah, there are even human-powered aircraft. But you're not going to power jet aircraft with pedal power, are you? The largest aircraft in your examples seems to be a two-seater prop plane.

I don't know of any alternative to power many of our planes besides carbon-based fuels. We can fly jets with biofuels today. Let me know when there's a large jet that runs off hydrogen, solar, or electric. Until then, we certainly are looking for carbon-based fuels.

Let me know when there's a large jet that runs off hydrogen, solar, or electric.Nice job moving the goalpost. It used to be "airplanes", now it's airliners.

But it's irrelevant. Airplanes need thrust. They get thrust from engines. Today's commercially-available engines burn fossil/carbon fuels, but in no way does that prevent us from putting a different engine on future planes.

No, it doesn't prevent us putting different engine on future planes. On the other hand, the other forms of energy do not have as high an energy density as carbon-based fuels, so they are are not practical to power planes. That is why we are looking for carbon-based fuels to replace fossil fuels.

None of those will work in a modern cargo or passenger jet, except perhaps hydrogen. Then only in liquid form would it have sufficient density, which means your handing super cold crygenic liquids. They're a looooong way from being able to use that in commercial jets. So, you need to consider what we can do now, today, which is carbon-based bio-fuels.

and I gave you the answer, minimum carbon and maximum hydrogen per molecule. Methane or methanol are very efficient ways to store hydrogen. As compared to oil or coal, burning methane (or methanol) produces less CO2 per unit of energy. Because of it's short half-life in the atmosphere (7 years), you might be better off in the long run handling methane and risking the small percent leakage than burning coal and dumping over twice as much CO2 into the atmosphere, given CO2's 10,000 year half-li

So, if this works, would we then have whole artifical forests creating hydrogen and methanol? How safe would these things be? I imagine a forest would require access to sunlight, but it's somewhat difficult to have proper safeguards on a place that has a big window in it. And with these "trees" being full of methanol/hydrogen, one spark or too MUCH sun/heat and the whole place goes up like a bomb.

So, if this works, would we then have whole artifical forests creating hydrogen and methanol? How safe would these things be?

Tell you what -- when someone proposes actually building an "artificial hydrogen forest", we'll have a look at the blueprints they provide and discuss potential safety hazards and how to mitigate them. Until then, worrying about what might happen in a hypothetical energy plant that might be built some decades from, if the basic research (that has not even started yet) comes to frui

I knew an environmental engineer once who told me plants are actually inefficient at converting energy... Maybe he was mistaken, anyone know?
Besides doesn't this already exist? I thought Solar panels generated electricity that could be used to charge batteries or produce hydrogen.

He was correct. Certain steps in the photosynthetic process are very efficient, but the fact that only part of sunlight is photosynthetically active, the fact that plants don't process all light that hits them, and that not all energy they produce goes into biomass, generally limits the total biomass yield to 3-6%. Food crops generally yield between a fraction of a percent and a couple percent of the solar energy that hits them as food, but practical growth limitations make that even lower (by a good margin). To give an example of how that comes into play, sugarcane is a rare photosynthesis exception, at about 8% efficiency turning sunlight to biomass, but only 0.13% solar efficiency [wikipedia.org] to ethanol. That's 4000 liters per hectare of 225W/m^2 insolation land. That's 7.1e13 joules of solar energy to prduce 9.36e10 joules of ethanol. Awful efficiency, no?

yup... However, using highly efficient carbon nuetral energy sources (wind, water, solar, etc) to make energy to power high luminocity limited spectrum bulbs we might be able to work it out. That, or redirect only specific wavelengths into the chemical process and the rest to solar colectors through the use of prisms/filters.

That said, what do they REALLY plan to do with the H2 produced? Lets face it, we'll not be running our cars on it likely for more than 100 years, if ever. Even if you could make H2

Wasting wind power to create hydrogen through electrolysis(only 60% efficient) and then using more energy to futher convert it into liquid fuel to burn in conventional engines(20% efficient) might make sense if we had a large excess of wind energy. The problem is that while wind energy is clean and there are many good locations to site wind farms in the US the amount of electricity produced does not come close to meeting our demands for clean electricity. Maintaining our traditional reliance on liquid fuels

yea clearly did not follow the link. We actually have a SERIOUS problem in this country PREVENTING further rollout of Wind energy, and it's called off-peak losses.

Wind power companies are litterally PAYING people to take the energy they produce during off-peak hours. Until we finish deploying an interconencted national grid, and until we depoloy a storage system for overproduced energy, local wind farms are suffering when they're actually producing more than the local markets can bear in energy. The elec

Battery powered vehicles can NOT replace fuel cars for 30-50 year until we build YET MORE power sources, and figure out how to handle the MASSIVE swings in usage that would come with 100million cars sucking from the grid at odd hours...

BEVs take *one third as much power* to operate as H2 FCVs and *one fifth as much* as H2 ICEs. They *stabilize the grid*, because they're steady sources that mainly charge during... wait for it... off peak hours.

1/3rd as much power huh? in terms of joules or BTUs, yes, but where one power source is coming from the ground, the other is coming from power plants, and we don't have those power plants!

Also, the local grids (last mile) can't handle that extra load...

Also off-peak is NOT considered "night time" but varies by region and time of year. in the summer, off-peak is typically midnight to 5AM. but BEVs take 8-10 hours to charge, oops.In the winter, off-peak is 9AM to 4PM! the car's not home, oops...

1/3rd as much power huh? in terms of joules or BTUs, yes, but where one power source is coming from the ground, the other is coming from power plants, and we don't have those power plants!

1) Hydrogen isn't "coming from the ground".2) We *do* have those power plants, according to the DOE.

Also, the local grids (last mile) can't handle that extra load...

3) Since when? Even a full recharge to a Volt every night -- 8kWh plus a little more for conversion losses (say, 9kWh total) -- can be done on a single normal 110V socket in 6 hours. How exactly is that going to tax the local grids?

Also off-peak is NOT considered "night time" but varies by region and time of year. in the summer, off-peak is typically midnight to 5AM. but BEVs take 8-10 hours to charge, oops.

"Oops yourself". First off, "Off peak" generally starts at around 11:00 and ends at around 6:00. 12 to 5 is just somewhat deeper of an off-peak than 11 to 6, but you're definitely not going to overload the grid. Secondly, 8-10 hours on even a 110V/15A socket (and a 110V/15A will *not* overload the grid) is 48 to 60 miles range per day. Only a small fraction of the US population drives that much. If you want to talk, say, dryer socket-level charging, even 100 miles of range is just over four hours.

Also, once we move to fast charge, it will NOT be stady, stable off-peak loads.

That's not how fast charge works. Commercial fast chargers tend to have battery banks that they draw from. The banks are trickle charged (and ideally, smart-charged).

Also, if you read the link's data, they are NOT storing H2, they're making it as part of a catalytic process.

A) What link are you talking about?B) Hydrogen cannot be made "in a catalytic process". It's an energy sink, not a source.

It's only kept in short term, low pressure tanks for 12-36 hours.

Doesn't matter. It's still hugely expensive. So is large-scale hydrogen production and compression equipment.

These types of tanks are CHEAP

They absolutely are not. Hydrogen tanks are typically composite (since they embrittle metals). Often carbon fiber with a polymer lining. Show me a large, cheap carbon fiber tank and I'll show you a living unicorn.

efficient

Nonsense. Electrolysis is 50-80% efficient (with the more efficient systems being more expensive due to lower throughput), and you generally lose 10-20% of the remaining energy in compression. Then you have the fuel cells at 40-60% efficiency (you can get slightly higher in the lab, but that's only under controlled conditions, with pre-compressed oxygen rather than uncompressed air). Or you have an H2 ICE generator, at ~40% efficiency.

and have extremely little leakage

Hydrogen leaks through steel at about 100 times the rate propane does (which is positively a leaker compared to gasoline). It is the easiest chemical on the world to leak, bar none.

EV batteries contain toxins, rare chemicals, and though the most recent technologies are highly recyclable, its a messy expensive process, not to mentoin LiIon pack failure and fires...

Wrong on every front. One, the types of batteries mainly being used for EVs today are lithium iron phosphate and manganese spinels. Neither of these are toxic. You can legally just throw them straight in the trash. Two, they contain no "rare chemicals" (fuel cells do, however! They use platinum). Three, the recycling process is neither "messy" nor "expensive"; most packs are having their recycling costs included in the purchase price. Four, LiP and LiMnO2 cells have almost no fire risk, unlike the LiCoO2 cells that most people are familiar with from laptops and cell phones (only Tesla is using those).

I also read the DOE result when it came out recently, and there are a few things you should note: 1) the study completely ignored local grid distribution, and was a statement of average available energy across the USA (total poewr p

1) no, OIL comes from the ground... the 1/3rd number refered to oil being 1/3 less effecient than EV.2) We have the TOTAL capacity, IF we run 100% of our plants at 100% peak output and IF we can stagger the load across those 24 hours... That's not possible.

Oil is not hydrogen. Oil can be used to produce hydrogen, but if you're going to do that, why bother?

We have the TOTAL capacity, IF we run 100% of our plants at 100% peak output and IF we can stagger the load across those 24 hours... That's not possible.

Straw man. Of the major sources on our grid, only wind, hydro, and solar can't be run close to 100%, and they make up a small percent of the total. The rest can all be run at near 100%. With our current grid, we can gen

Wasting wind power to create hydrogen through electrolysis(only 60% efficient)

Actually, despite the lack of efficiency, that might be a good way to store any excess energy produced by the wind turbine. When the demand picks up then you can reconvert it to electricity using fuel cells.

If only facilities to create and store hydrogen were free to build and maintain, rather than being hugely expensive as they are in real life. And way less efficient than just storing it in EV batteries at night (which the grid operators get at no extra charge to themselves).

That only works if the EV batteries 1.) exist in large numbers and 2.) are allowed to be used that way. There's lots of talk about using consumer's EV batteries for energy storage on the grid; but, personally I'm not real wild about the electric utility running the expensive battery in my car through extra charge and discharge cycles.

There's no (zero) doubt that utilizing large scale wind power requires an energy storage system to balance out demand vs available wind. Current suggested plans use such me

Think about the 'natural' process for creating oil: Take millions of plants using photosynthesis to create carbon based material. Run for millions of years, accumulating the product. Then put a mountain on top of it, shove it deep under the Earth. Apply tremendous heat and pressure for millions of years more. Remove mountain top and extract.

So even if we are able to copy photosynthesis, what does it get us? We use energy several hundred million times faster

granted, if we can understand the process with which wavelengths of light are used to convert matter using catylists, we can design a more efficient process based on it, likely using substrates and not actual biological processes.

That said, we get H2, which other than being burned directly on site has little value to the rest of ut. We can NOt afford to use it in our cars, ever. It costs too much to build an infrastructure, we have to reengineer all the cars, and it's WAY too dangerous. instead, we could

You are alone in this view. The accepted source of the creation of oil is organic matter under high heat and pressure. The unaccepted contrary view is it is an abiotic process. Nobody except you claims it is made by microorganisms.

From Wikipedia:crude oil and natural gas are products of heating of ancient organic materials (i.e. kerogen) over geological time. Formation of petroleum occurs from hydrocarbon pyrolysis, in a variety of mostly e

Seems a bit daft to create methane and other organic molecules using sunlight, and then burn the methane to make hydrogen for use a fuel cells! If methane is produced, then why not burn it directly for maximum efficiency. Or convert methane into a heavier, gasoline-like molecule to burn in a conventional engines.

it's a game you play with the efficiency numbers. IF, it turns out that the fuel cell is sufficiently more efficient than the engine + generator, then you burn the methane to make hydrogen for the fuel cell. Of course to do this you have to have a reliable efficient fuel cell.

I can't find a reference to it, but I saw a segment on a TV show (I think "Your Green Life", which according to the local station, is nationally syndicated) about a company that was already working on a device that mimicked photosynthesis. I seem to remember the device looks sort of like venetian blinds.

Does anybody else remember seeing that segment or have more info about that company?

This is obviously a fascinating concept, but I wonder how realistic its chances of succeeding are. As well as what "success" would actually mean.
If my math is correct, 0.16% of Earth's [wikipedia.org] surface area (510,072,000 sq. km) is 816,115.2 sq. km. That's larger than the state of Texas, and sounds like a lot of artificial leaves.
As for defining success, today, civilization relies on various methods of generating the power it needs. Yet the mainstream press continue to often "pressure" highly speculative energy s